/* body 样式，确保容器居中 */
body {
    background-image: url('/static/download.jpg');
    background-size: cover;
    background-repeat: no-repeat;
    background-position: center;
    height: 100vh;
    color: white;
    margin: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    font-family: Arial, sans-serif;
}
.container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    max-width: 500px; /* 扩大容器宽度 */
    padding: 60px; /* 增加容器的内边距 */
    background-color: rgba(0, 0, 0, 0.4); /* 更深的背景色 */
    border-radius: 10px;
    box-shadow: 0 6px 15px rgba(0, 0, 0, 0.1); /* 增强阴影效果 */
}
.back-button {
    position: absolute;
    top: 30px; /* 增加返回按钮的顶部间距 */
    left: 30px; /* 增加左侧间距 */
    font-size: 2em; /* 增大字体 */
    color: white;
    text-decoration: none;
    padding: 15px;
    z-index: 1000;
}
.back-button:hover {
    color: lightgray;
}
.title {
    font-size: 2.5em; /* 增大标题字体 */
    font-weight: bold;
    margin-bottom: 40px; /* 增大标题底部间距 */
    text-align: center;
}
.form-group {
    width: 100%;
    margin-bottom: 20px; /* 增大输入框间距 */
    display: flex;
    justify-content: center;
}
.form-group input {
    width: 100%;
    max-width: 350px; /* 扩大输入框宽度 */
    padding: 12px 24px; /* 增加内边距 */
    background-color: white;
    border: none;
    border-radius: 30px; /* 更大的圆角 */
    color: black;
    text-align: center;
    font-size: 1.2em; /* 增大字体 */
}
.form-group input::placeholder {
    color: black;
}
/* 按钮组容器的样式 */
.btn-group-custom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
    max-width: 350px; /* 扩大按钮组的最大宽度 */
    margin-top: 30px; /* 增大按钮组的顶部间距 */
    gap: 15px; /* 增大按钮之间的间距 */
}
/* 按钮的样式 */
.btn-custom {
    flex: 1;
    padding: 15px 0; /* 增大按钮的上下内边距 */
    border-radius: 30px; /* 更大的圆角 */
    background-color: white;
    color: black;
    font-size: 1.2em; /* 增大字体 */
    text-align: center;
    border: 2px solid white;
    cursor: pointer;
    text-decoration: none;
    text-align: center;
}
.btn-custom:hover {
    background-color: #f0f0f0;
    color: black;
}
.flash-message {
    width: 100%;
    max-width: 350px; /* 扩大提示框宽度 */
    margin-top: 15px;
    margin-left: auto;
    margin-right: auto;
    text-align: center;
}